backlight brightness control interface if it detects that the standard
ACPI interface is available in the ThinkPad.
+If you want to use the thinkpad-acpi backlight brightness control
+instead of the generic ACPI video backlight brightness control for some
+reason, you should use the acpi_backlight=vendor kernel parameter.
+
The brightness_enable module parameter can be used to control whether
the LCD brightness control feature will be enabled when available.
brightness_enable=0 forces it to be disabled. brightness_enable=1